The purpose of this study was to determine if there is a relationship between the classroom organizational structure and MCT2 test scores of fifth-grade math students. The researcher gained insight regarding which structure teachers believe is most beneficial to them and students, and whether or not their belief of classroom organizational structure differs based on the number of years of classroom experience and/or degree held. The results of this study showed no significant difference in the standardized test scores of students in a self-contained classroom compared to the students in a departmentalized classroom. Though there was no significant difference in teachers' beliefs relative to differences and possible benefits between the self-contained and departmentalized classrooms, teachers did display optimism in regard to departmentalization in the fifth-grade math classroom. No significant difference was found in teachers' beliefs about classroom organizational structure based on years of classroom experience or current classroom structure, however, there was a significant difference in regards to teachers' beliefs about classroom organizational structure and their certification level. No significant difference in the classroom organizational structure and standardized test scores was found, but teachers were more optimistic in regard to the departmentalized classroom. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]